1. Field of the Invention
The present invention relates to a force-feedback input device that applies, to an operation section, force feedback in accordance with the operating state of the operation section, and more particularly, to means for updating part data, which is used as a basis for applying the force feedback.
2. Description of the Related Art
Conventionally, a force-feedback input device is known as an input device applied to, for example, so-called by-wire devices, such as a central control device for car-mounted electric devices, such as a steering device, a gearshift device, or a brake device. Such input devices include an operation section to be operated by an operator, a position detection section for detecting an operating state of the operation section, a force-feedback generation section for applying force feedback to the operation section, a display section for displaying the operating state and the operation contents of the operation section, and a haptic commander for controlling the driving of the force-feedback generation section, applying force feedback to the operation section according to the operating state thereof, and controlling the driving of the display section (for example, refer to Japanese Unexamined Patent Application Publication No. 2001-84875 (see FIG. 1)).
According to this force-feedback input device, since various force feedbacks in accordance with the direction, amount, or the like of the operation can be applied to the operation section by driving the force-feedback generation section, a required operation sensation can be given to the operation of the operation section in various by-wire devices.
The application of force feedback to the operation section in a central control device for car-mounted electric devices is performed in such a manner that, when the car-mounted electric device is selected or the function of the car-mounted electric device is selected as a result of operating the operation section, a force-feedback pattern in accordance with the selected car-mounted electric device or the function of the selected car-mounted electric device is set in the haptic commander.
For example, in a case where a central control device for car-mounted electric devices is activated, and the selection button of the type of car-mounted electric device, which can be controlled by the central control device, for example, an air conditioner, a CD player, an MD player, a DVD player, a radio, a television, a telephone, and a car navigation system, and the cursor are displayed on the display section, force-feedback patterns are set in the haptic commander. Examples of the force-feedback patterns are a wall surface for guiding, from a predetermined position, the operation section only in eight directions, which are the arrangement directions of each selection button, a retraction point at which the cursor is retracted to the center position of each selection button, a damper for providing, to the operation of the operation section, a sensation of expanding or compressing a spring, and a friction force of providing a fixed resisting sensation to the operation of the operation. When, for example, an air conditioner is selected by selecting the selection button, selection buttons for indicating temperature, the amount of wind, and the blowoff opening, which are adjustable in the air conditioner, and the cursor are displayed on the next screen, and a force-feedback pattern including a wall surface for guiding, from a predetermined position, the operation section only in three directions, which are arrangement directions of each selection button, is set in the haptic commander.
Methods for setting a force-feedback pattern in the haptic commander include a part data transmission method for transmitting part data used to generate a required force-feedback pattern to the haptic commander from an external device, such as a microcomputer, to which the force-feedback input device is connected, each time the display screen is changed, and a force-feedback table storage method having tables corresponding to force-feedback patterns formed in such a manner that required part data transmitted from an external device to the haptic commander is combined.
The setting of a force-feedback pattern by the part data transmission method has the advantages that, since adjustment of a set position, correction of a shape, correction of a force generation parameter, etc., are possible in units of part data, a force-feedback pattern that is easy for an operator to use can be easily generated, and since part data created at an external device is transmitted to the haptic commander, the addition of a force-feedback pattern can be easily performed. On the other hand, the part data transmission method has the disadvantages that, since required part data must be transmitted from an external device to the haptic commander each time the display screen is changed, the larger the number of pieces of part data to be transmitted, the longer the transmission time of the part data, and when a control method in which force feedback is not generated unless all the part data is transmitted is adopted, the switching response of the force-feedback pattern becomes deteriorated. Furthermore, in a case where a control method in which force feedback based on the transmitted part data is generated each time the transmission of each piece of the part data is completed is adopted, since undesirable force feedback acts on the operation section depending on the transmitted part data, disadvantages arise in that the ease of operation of the operation section becomes deteriorated.
On the other hand, for the setting of a force-feedback pattern by the force-feedback table storage method, a desired force-feedback pattern can be set by merely transmitting a command indicating a desired table number to the haptic commander from an external device, and desired force-feedback patterns can be activated collectively as a whole rather than in units of part data, thus making it possible to overcome the disadvantages of the part data transmission method. But nevertheless, since the haptic commander must be provided with a large-capacity storage device, another disadvantage arises in that the cost of the force-feedback input device is increased. Also, since the force-feedback patterns are handled as a whole rather than in units of part data, in order to change the set position, the shape, and the force generation pattern, and so forth of part data, updating of all the part data stored in the table becomes necessary, and there is a disadvantage in that the correction of the part data cannot be easily performed. Furthermore, in order to enable the addition of a force-feedback pattern that can be handled by the force-feedback input device, an expensive data recordable or rewritable storage device is required, and if an inexpensive read-only storage device is provided to achieve a lower cost of the force-feedback input device, the addition of a force-feedback pattern by a user (operator) becomes impossible, and there is thus another disadvantage in that the expandability of functions is limited.